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1.
Sci Immunol ; 9(94): eadi8039, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38579013

RESUMO

Vaccine adjuvants increase the breadth of serum antibody responses, but whether this is due to the generation of antigen-specific B cell clones with distinct specificities or the maturation of memory B cell clones that produce broadly cross-reactive antibodies is unknown. Here, we longitudinally analyzed immune responses in healthy adults after two-dose vaccination with either a virus-like particle COVID-19 vaccine (CoVLP), CoVLP adjuvanted with AS03 (CoVLP+AS03), or a messenger RNA vaccination (mRNA-1273). CoVLP+AS03 enhanced the magnitude and durability of circulating antibodies and antigen-specific CD4+ T cell and memory B cell responses. Antigen-specific CD4+ T cells in the CoVLP+AS03 group at day 42 correlated with antigen-specific memory B cells at 6 months. CoVLP+AS03 induced memory B cell responses, which accumulated somatic hypermutations over 6 months, resulting in enhanced neutralization breadth of monoclonal antibodies. Furthermore, the fraction of broadly neutralizing antibodies encoded by memory B cells increased between day 42 and 6 months. These results indicate that AS03 enhances the antigenic breadth of B cell memory at the clonal level and induces progressive maturation of the B cell response.


Assuntos
COVID-19 , Vacinas contra Influenza , Influenza Humana , Polissorbatos , Esqualeno , alfa-Tocoferol , Adulto , Humanos , Células B de Memória , Vacinas contra COVID-19 , Anticorpos Antivirais , COVID-19/prevenção & controle , Combinação de Medicamentos
2.
Nat Commun ; 15(1): 1742, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453921

RESUMO

Super Typhoon Mangkhut, which traversed the North Equatorial Current (NEC; 8-17 °N) in the western North Pacific in 2018, was the most intense Category-5 tropical cyclone (TC) with the longest duration in history-3.5 days. Here we show that the combination of two factors-high ocean heat content (OHC) and increased stratification - makes the NEC region the most favored area for a rapid intensification (RI) of super typhoons, instead of the Eddy Rich Zone (17-25 °N), which was considered the most relevant for RI occurrence. The high OHC results from a northward deepening thermocline in geostrophic balance with the westward-flowing NEC. The stratification is derived from precipitation associated with the Inter-Tropical Convergence Zone in the summer peak typhoon season. These factors, which are increasingly significant over the past four decades, impede the TC-induced sea surface cooling, thus enhancing RI of TCs and simultaneously maintaining super typhoons over the NEC region.

3.
Bioengineering (Basel) ; 11(1)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38247941

RESUMO

Many colonic surgeries include colorectal anastomoses whose leaks may be life-threatening, affecting thousands of patients annually. Various studies propose that mechanical interaction between the staples and neighboring tissues may play an important role in anastomotic leakage. Therefore, understanding the mechanical behavior of colorectal tissue is essential to characterizing the reasons for this type of failure. So far, experimental data characterizing the mechanical properties of colorectal tissue have been few and inconsistent, which has significantly limited understanding their behavior. This research proposes an approach to developing an anisotropic hyperelastic material model for colorectal tissues based on uniaxial testing of freshly harvested porcine specimens, which were collected from several age- and weight-matched pigs. The specimens were extracted from the same colon tract of each pig along their circumferential and longitudinal orientations. We propose a constitutive model combining Yeoh isotropic hyperelastic material with fibers oriented in two directions to account for the hyperelastic and anisotropic nature of colorectal tissues. Experimental data were used to accurately determine the model's coefficients (circumferential, R2 = 0.9968; longitudinal, R2 = 0.9675). The results show that the proposed model can be incorporated into a finite element model that can simulate procedures such as colorectal anastomoses reliably.

4.
Microbiol Spectr ; 12(2): e0310922, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38189293

RESUMO

Developing a vaccine against Clostridioides difficile is a key strategy to protect the elderly. Two candidate vaccines using a traditional approach of intramuscular (IM) delivery of recombinant antigens targeting C. difficile toxins A (TcdA) and B (TcdB) failed to meet their primary endpoints in large phase 3 trials. To elicit a mucosal response against C. difficile, we repurposed an attenuated strain of Salmonella Typhimurium (YS1646) to deliver the receptor binding domains (rbd) of TcdA and TcdB to the gut-associated lymphoid tissues, to elicit a mucosal response against C. difficile. In this study, YS1646 candidates with either rbdA or rbdB expression cassettes integrated into the bacterial chromosome at the attTn7 site were generated and used in a short-course multimodal vaccination strategy that combined oral delivery of the YS1646 candidate(s) on days 0, 2, and 4 and IM delivery of recombinant antigen(s) on day 0. Five weeks after vaccination, mice had high serum IgG titers and increased intestinal antigen-specific IgA titers. Multimodal vaccination increased the IgG avidity compared to the IM-only control. In the mesenteric lymph nodes, we observed increased IL-5 secretion and increased IgA+ plasma cells. Oral vaccination skewed the IgG response toward IgG2c dominance (vs IgG1 dominance in the IM-only group). Both oral alone and multimodal vaccination against TcdA protected mice from lethal C. difficile challenge (100% survival vs 30% in controls). Given the established safety profile of YS1646, we hope to move this vaccine candidate forward into a phase I clinical trial.IMPORTANCEClostridioides difficile remains a major public health threat, and new approaches are needed to develop an effective vaccine. To date, the industry has focused on intramuscular vaccination targeting the C. difficile toxins. Multiple disappointing results in phase III trials have largely confirmed that this may not be the best strategy. As C. difficile is a pathogen that remains in the intestine, we believe that targeting mucosal immune responses in the gut will be a more successful strategy. We have repurposed a highly attenuated Salmonella Typhimurium (YS1646), originally pursued as a cancer therapeutic, as a vaccine vector. Using a multimodal vaccination strategy (both recombinant protein delivered intramuscularly and YS1646 expressing antigen delivered orally), we elicited both systemic and local immune responses. Oral vaccination alone completely protected mice from lethal challenge. Given the established safety profile of YS1646, we hope to move these vaccine candidates forward into a phase I clinical trial.


Assuntos
Toxinas Bacterianas , Compostos de Boro , Clostridioides difficile , Humanos , Animais , Camundongos , Idoso , Toxinas Bacterianas/genética , Salmonella typhimurium/genética , Clostridioides difficile/genética , Vacinas Bacterianas , Vacinas Sintéticas , Vacinação , Imunoglobulina G , Imunoglobulina A
5.
JAMA Intern Med ; 184(1): 18-27, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-37306992

RESUMO

Importance: Despite widespread use, summary evidence from prior meta-analyses has contradictory conclusions regarding whether oseltamivir decreases the risk of hospitalization when given to outpatients. Several large investigator-initiated randomized clinical trials have not yet been meta-analyzed. Objective: To assess the efficacy and safety of oseltamivir in preventing hospitalization among influenza-infected adult and adolescent outpatients. Data Sources: PubMed, Ovid MEDLINE, Embase, Europe PubMed Central, Web of Science, Cochrane Central, ClinicalTrials.gov, and WHO International Clinical Trials Registry were searched from inception to January 4, 2022. Study Selection: Included studies were randomized clinical trials comparing oseltamivir vs placebo or nonactive controls in outpatients with confirmed influenza infection. Data Extraction and Synthesis: In this systematic review and meta-analysis, Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) reporting guidelines were followed. Two independent reviewers (R.H. and É.B.C.) extracted data and assessed risk of bias using the Cochrane Risk of Bias Tool 2.0. Each effect size was pooled using a restricted maximum likelihood random effects model. The quality of evidence was graded using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) framework. Main Outcomes and Measures: Hospitalization was pooled as risk ratio (RR) and risk difference (RD) estimates with 95% CIs. Results: Of 2352 studies identified, 15 were included. The intention-to-treat infected (ITTi) population was comprised of 6166 individuals with 54.7% prescribed oseltamivir. Across study populations, 53.9% (5610 of 10 471) were female and the mean age was 45.3 (14.5) years. Overall, oseltamivir was not associated with reduced risk of hospitalization within the ITTi population (RR, 0.79; 95% CI, 0.48 to 1.29; RD, -0.17%; 95% CI, -0.23% to 0.48%). Oseltamivir was also not associated with reduced hospitalization in older populations (mean age ≥65 years: RR, 1.01; 95% CI, 0.21 to 4.90) or in patients considered at greater risk of hospitalization (RR, 0.65; 0.33 to 1.28). Within the safety population, oseltamivir was associated with increased nausea (RR, 1.43; 95% CI, 1.13 to 1.82) and vomiting (RR, 1.83; 95% CI, 1.28 to 2.63) but not serious adverse events (RR, 0.71; 95% CI, 0.46 to1.08). Conclusions and Relevance: In this systematic review and meta-analysis among influenza-infected outpatients, oseltamivir was not associated with a reduced risk of hospitalization but was associated with increased gastrointestinal adverse events. To justify continued use for this purpose, an adequately powered trial in a suitably high-risk population is justified.


Assuntos
Influenza Humana , Oseltamivir , Adulto , Adolescente , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Masculino , Oseltamivir/efeitos adversos , Influenza Humana/tratamento farmacológico , Influenza Humana/prevenção & controle , Pacientes Ambulatoriais , Hospitalização , Europa (Continente)
6.
Plant Dis ; 108(1): 149-161, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37578368

RESUMO

Cercospora leaf blight (CLB) of soybean, caused by Cercospora cf. flagellaris, C. kikuchii, and C. cf. sigesbeckiae, is an economically important disease in the southern United States. Cultivar resistance to CLB is inconsistent; therefore, fungicides in the quinone outside inhibitor (QoI) class have been relied on to manage the disease. Approximately 620 isolates from plants exhibiting CLB were collected between 2018 and 2021 from 19 locations in eight southern states. A novel polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay based on two genes, calmodulin and histone h3, was developed to differentiate between the dominant species of Cercospora, C. cf. flagellaris, and C. cf. sigesbeckiae. A multilocus phylogenetic analysis of actin, calmodulin, histone h3, ITS rDNA, and transcription elongation factor 1-α was used to confirm PCR-RFLP results and identify remaining isolates. Approximately 80% of the isolates collected were identified as C. cf. flagellaris, while 15% classified as C. cf. sigesbeckiae, 2% as C. kikuchii, and 3% as previously unreported Cercospora species associated with CLB in the United States. PCR-RFLP of cytochrome b (cytb) identified QoI-resistance conferred by the G143A substitution. Approximately 64 to 83% of isolates were determined to be QoI-resistant, and all contained the G143A substitution. Results of discriminatory dose assays using azoxystrobin (1 ppm) were 100% consistent with PCR-RFLP results. To our knowledge, this constitutes the first report of QoI resistance in CLB pathogen populations from Alabama, Arkansas, Kentucky, Mississippi, Missouri, Tennessee, and Texas. In areas where high frequencies of resistance have been identified, QoI fungicides should be avoided, and fungicide products with alternative modes-of-action should be utilized in the absence of CLB-resistant soybean cultivars.


Assuntos
Ascomicetos , Fungicidas Industriais , Estados Unidos , Fungicidas Industriais/farmacologia , Cercospora , Glycine max , Filogenia , Calmodulina/genética , Histonas/genética , Arkansas , Quinonas
7.
Vaccine ; 42(3): 713-722, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38142214

RESUMO

INTRODUCTION: Cytomegalovirus (CMV) is the most common cause of congenital infection and affected children often have permanent neurodevelopmental sequelae, including hearing loss and intellectual disability. Vaccines to prevent transmission of CMV during pregnancy are a public health priority. This first-in-humans dose-ranging, randomized, placebo-controlled, observer-blinded study evaluated the safety and immunogenicity of an enveloped virus-like particle (eVLP) vaccine expressing a modified form of the CMV glycoprotein B (gB). METHODS: Healthy CMV-seronegative 18 to 40-year-olds at 3 Canadian study sites were randomized to one of 4 dose formulations (0.5 µg, 1 µg, or 2 µg gB content with alum) or 1 µg gB without alum, or placebo, given intramuscularly on days 0, 56 and 168. Outcome measures were solicited and unsolicited adverse events (AE), severe AE, gB and AD-2 epitope binding antibody titers and avidity, and neutralizing antibody (nAb) titers to CMV measured in fibroblast and epithelial cell infection assays. RESULTS: Among 125 participants, the most common solicited local and general AEs were pain and headache, respectively. A dose-dependent increase in gB binding, avidity and nAb titers was observed after doses 2 and 3, with the highest titers in the alum-adjuvanted 2.0 µg dose recipients after the third dose; in the latter 24 % had responses to the broadly neutralizing AD-2 epitope. Neutralizing activity to CMV infection of fibroblasts was seen in 100 % of 2.0 µg alum-adjuvanted dose recipients, and to epithelial cell infection in 31 %. Epithelial cell nAb titers were positively correlated with higher geometric mean CMV gB binding titers. CONCLUSIONS: An eVLP CMV vaccine was immunogenic in healthy CMV-seronegative adults and no safety signals were seen. Alum adjuvantation increased immunogenicity as did higher antigen content and a three dose schedule. This phase 1 trial supports further development of this eVLP CMV vaccine candidate.


Assuntos
Compostos de Alúmen , Infecções por Citomegalovirus , Vacinas contra Citomegalovirus , Vacinas de Partículas Semelhantes a Vírus , Adulto , Criança , Gravidez , Feminino , Humanos , Citomegalovirus , Anticorpos Antivirais , Canadá , Infecções por Citomegalovirus/prevenção & controle , Vacinação , Hidróxido de Alumínio , Adjuvantes Imunológicos , Epitopos , Anticorpos Neutralizantes , Imunogenicidade da Vacina
8.
Viruses ; 15(12)2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-38140601

RESUMO

Molluscum contagiosum (MC) is characterized by skin lesions containing the highly contagious molluscum contagiosum poxvirus (MCV). MCV primarily infects children, with one US Food and Drug Administration (FDA)-approved drug-device treatment in use but no approved medications. Assessing antivirals is hindered by the inability of MCV to replicate in vitro. Here, we use vaccinia virus as a surrogate to provide evidence of the anti-poxvirus properties of berdazimer sodium, a new chemical entity, and the active substance in berdazimer gel, 10.3%, a nitric oxide-releasing topical in phase 3 development for the treatment of MC. We show that berdazimer sodium reduced poxvirus replication and, through a novel methodology, demonstrate that cells infected with drug-treated MCV virions have reduced early gene expression. Specifically, this is accomplished by studying the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-kB)-blocking protein MC160 as an example of an early gene. The results provide a plausible unique antiviral mechanism of action supporting increased MCV resolution observed in patients treated with berdazimer gel, 10.3% and describe a novel methodology that overcomes limitations in investigating MCV response in vitro to a potential new MC topical medication.


Assuntos
Molusco Contagioso , Vírus do Molusco Contagioso , Estados Unidos , Criança , Humanos , Vírus do Molusco Contagioso/genética , Molusco Contagioso/tratamento farmacológico , Siloxanas/metabolismo , Antivirais/farmacologia , Antivirais/metabolismo
9.
Vaccine ; 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37827968

RESUMO

On November 18-19, 2019, the Immunity of Canadians and Risk of Epidemics (iCARE) Network convened a workshop in Toronto, Ontario, Canada. The objectives of the workshop were to raise the profile of sero-epidemiology in Canada, discuss best practice and methodological innovations, and strategize on the future direction of sero-epidemiology work in Canada. In this conference report, we describe the presentations and discussions from the workshop, and comment on the impact of the COVID-19 pandemic on serosurveillance initiatives, both in Canada and abroad.

10.
Vital Health Stat 1 ; (204): 1-45, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37751520

RESUMO

This report outlines the methodology, development, and fielding of the 2021 Physician Pain Management Questionnaire (PPMQ) pilot study. The study was conducted by the National Center for Health Statistics and was designed to test the feasibility of a large, nationally representative survey assessing physician awareness and use of established guidelines for prescribing opioids to manage pain.


Assuntos
Manejo da Dor , Médicos , Humanos , Analgésicos Opioides/efeitos adversos , Dor , Projetos Piloto , Estados Unidos , Estudos de Viabilidade
12.
Vaccine ; 41(41): 6008-6016, 2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37625992

RESUMO

BACKGROUND: Norovirus (NoV) is the most common cause of diarrheal episodes globally. Issues with in vitro cultivation systems, genetic variation, and animal models have hindered vaccine development. Plant-derived virus-like particles (VLPs) may address some of these concerns because they are highly immunogenic, can be administered by different routes, and can be rapidly produced to accommodate emerging viral strains. METHODS: NoV VLPs (NoVLP) composed of the surface viral protein (VP) 1 of the GI and GII genogroups were produced in Nicotiana benthamiana using an Agrobacterium tumefaciens-based recombinant transient expression system. Leaves from infiltrated plants were harvested and NoVLPs were extracted and purified. The safety and immunogenicity of the GII.4 NoVLP, the genotype currently causing most human disease, were subsequently examined in rabbits and mice. RESULTS: Fifteen GI and GII NoVLPs were successfully expressed in N. benthamiana and were structurally similar to NoV virions, as determined by cryogenic transmission electron microscopy. The NoVLP was well-tolerated, with no local or systemic signs of toxicity in rabbits. Three intramuscular doses of the GII.4 NoVLP adjuvanted with aluminum hydroxide induced robust IgG titers, IgG-secreting cells, histo-blood group antigen blocking titers, and IFNγ-secreting T cells in mice. In addition to circulating antibodies, oral administration of the NoVLP in mice induced significant IgA levels in feces, indicative of a mucosal response. CONCLUSIONS: The plant-made NoVLP vaccine was safe and immunogenic in mice and rabbits. Multi-modal vaccination, combining oral and intramuscular administration could be considered for future clinical development to maximize systemic and mucosal immune responses.


Assuntos
Infecções por Caliciviridae , Norovirus , Vacinas de Partículas Semelhantes a Vírus , Vacinas Virais , Humanos , Coelhos , Animais , Camundongos , Anticorpos Antivirais , Norovirus/genética , Imunoglobulina G
13.
J Exp Bot ; 74(21): 6749-6759, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37599380

RESUMO

The presence or absence of awns-whether wheat heads are 'bearded' or 'smooth' - is the most visible phenotype distinguishing wheat cultivars. Previous studies suggest that awns may improve yields in heat or water-stressed environments, but the exact contribution of awns to yield differences remains unclear. Here we leverage historical phenotypic, genotypic, and climate data for wheat (Triticum aestivum) to estimate the yield effects of awns under different environmental conditions over a 12-year period in the southeastern USA. Lines were classified as awned or awnless based on sequence data, and observed heading dates were used to associate grain fill periods of each line in each environment with climatic data and grain yield. In most environments, awn suppression was associated with higher yields, but awns were associated with better performance in heat-stressed environments more common at southern locations. Wheat breeders in environments where awns are only beneficial in some years may consider selection for awned lines to reduce year-to-year yield variability, and with an eye towards future climates.


Assuntos
Grão Comestível , Triticum , Triticum/genética , Fenótipo , Resposta ao Choque Térmico , Sudeste dos Estados Unidos
15.
Vital Health Stat 1 ; (203): 1-16, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37367198

RESUMO

As part of modernization efforts, in 2021 the National Ambulatory Medical Care Survey (NAMCS) began collecting electronic health records (EHRs) for ambulatory care visits in its Health Center (HC) Component. As a result, the National Center for Health Statistics (NCHS)needed to adjust the approaches used in the sampling design for the HC Component. This report provides details on these changes to the 2021-2022 NAMCS.


Assuntos
Registros Eletrônicos de Saúde , Instalações de Saúde , Humanos , Assistência Ambulatorial , Coleta de Dados/métodos , Pesquisas sobre Atenção à Saúde , Visita a Consultório Médico , Estados Unidos
17.
NPJ Vaccines ; 8(1): 13, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781879

RESUMO

Despite the success of existing COVID-19 vaccine platforms, the persistent limitations in global deployment of vaccines and waning immunity exhibited by many of the currently deployed vaccine platforms have led to perpetual outbreaks of SARS-CoV-2 variants of concern. Thus, there is an urgent need to develop new durable vaccine candidates, to expand the global vaccine pipeline, and provide safe and effective solutions for every country worldwide. Here we deeply profiled the functional humoral response induced by two doses of AS03-adjuvanted and non-adjuvanted plant-derived Coronavirus-like particle (CoVLP) vaccine candidate from the phase 1 clinical trial, at peak immunogenicity and six months post-vaccination. AS03-adjuvanted CoVLP induced robust and durable SARS-CoV-2 specific humoral immunity, marked by strong IgG1antibody responses, potent FcγR binding, and antibody effector function. Contrary to a decline in neutralizing antibody titers, the FcγR2A-receptor binding capacity and antibody-mediated effector functions, such as opsonophagocytosis, remained readily detectable for at least six months.

18.
NPJ Vaccines ; 8(1): 27, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36849453

RESUMO

Schistosomiasis threatens hundreds of millions of people worldwide. The larval stage of Schistosoma mansoni migrates through the lung and adult worms reside adjacent to the colonic mucosa. Several candidate vaccines are in preclinical development, but none is designed to elicit both systemic and mucosal responses. We have repurposed an attenuated Salmonella enterica Typhimurium strain (YS1646) to express Cathepsin B (CatB), a digestive enzyme important for the juvenile and adult stages of the S. mansoni life cycle. Previous studies have demonstrated the prophylactic and therapeutic efficacy of our plasmid-based vaccine. Here, we have generated chromosomally integrated (CI) YS1646 strains that express CatB to produce a viable candidate vaccine for eventual human use (stability, no antibiotic resistance). 6-8-week-old C57BL/6 mice were vaccinated in a multimodal oral (PO) and intramuscular (IM) regimen, and then sacrificed 3 weeks later. The PO + IM group had significantly higher anti-CatB IgG titers with greater avidity and mounted significant intestinal anti-CatB IgA responses compared to PBS control mice (all P < 0.0001). Multimodal vaccination generated balanced TH1/TH2 humoral and cellular immune responses. Production of IFNγ by both CD4+ and CD8+ T cells was confirmed by flow cytometry (P < 0.0001 & P < 0.01). Multimodal vaccination reduced worm burden by 80.4%, hepatic egg counts by 75.2%, and intestinal egg burden by 78.4% (all P < 0.0001). A stable and safe vaccine that has both prophylactic and therapeutic activity would be ideal for use in conjunction with praziquantel mass treatment campaigns.

19.
NPJ Vaccines ; 7(1): 142, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351931

RESUMO

The rapid spread of SARS-CoV-2 continues to impact humanity on a global scale with rising total morbidity and mortality. Despite the development of several effective vaccines, new products are needed to supply ongoing demand and to fight variants. We report herein a pre-specified interim analysis of the phase 2 portion of a Phase 2/3, randomized, placebo-controlled trial of a coronavirus virus-like particle (CoVLP) vaccine candidate, produced in plants that displays the SARS-CoV-2 spike glycoprotein, adjuvanted with AS03 (NCT04636697). A total of 753 participants were recruited between 25th November 2020 and 24th March 2021 into three groups: Healthy Adults (18-64 years: N = 306), Older Adults (≥65 years: N = 282) and Adults with Comorbidities (≥18 years: N = 165) and randomized 5:1 to receive two intramuscular doses of either vaccine (3.75 µg CoVLP/dose+AS03) or placebo, 21 days apart. This report presents safety, tolerability and immunogenicity data up to 6 months post-vaccination. The immune outcomes presented include neutralizing antibody (NAb) titres as measured by pseudovirion assay at days 21 and 42 as well as neutralizing antibody cross-reactivity to several variants of concern (VOCs): Alpha, Beta, Gamma, Delta, and Omicron (BA.1), up to 201 days post-immunization. Cellular (IFN-γ and IL-4 ELISpot) response data in day 21 and 42 peripheral blood are also presented. In this study, CoVLP+AS03 was well-tolerated and adverse events (AE) after each dose were generally mild to moderate and transient. Solicited AEs in Older Adults and Adults with Comorbidities were generally less frequent than in Healthy Adults and the reactogenicity was higher after the second dose. CoVLP+AS03 induced seroconversion in >35% of participants in each group after the first dose and in ~98% of participants, 21 days after the second dose. In all cohorts, 21-days after the second dose, NAb levels in sera against the vaccine strain were ~10-times those in a panel of convalescent sera. Cross-reactivity to Alpha, Beta and Delta variants was generally retained to day 201 (>80%) while cross-reactivity to the Gamma variant was reduced but still substantial at day 201 (73%). Cross-reactivity to the Omicron variant fell from 72% at day 42 to 20% at day 201. Almost all participants in all groups (>88%) had detectable cellular responses (IFN-γ, IL-4 or both) at 21 days after the second dose. A Th1-biased response was most evident after the first dose and was still present after the second dose. These data demonstrated that CoVLP+AS03 is well-tolerated and highly immunogenic, generating a durable (at least 6 months) immune response against different VOCs, in adults ≥18 years of age, with and without comorbidities.

20.
Nat Commun ; 13(1): 6905, 2022 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-36371408

RESUMO

As the SARS-CoV-2 pandemic evolves, vaccine evaluation needs to include consideration of both durability and cross-reactivity. This report expands on previously reported results from a Phase 1 trial of an AS03-adjuvanted, plant-based coronavirus-like particle (CoVLP) displaying the spike (S) glycoprotein of the ancestral SARS-CoV-2 virus in healthy adults (NCT04450004). Humoral and cellular responses against the ancestral strain were evaluated 6 months post-second dose (D201) as secondary outcomes. Independent of dose, all vaccinated individuals retain binding antibodies, and ~95% retain neutralizing antibodies (NAb). Interferon gamma and interleukin-4 responses remain detectable in ~94% and ~92% of vaccinees respectively. In post-hoc analyses, variant-specific (Alpha, Beta, Delta, Gamma and Omicron) NAb were assessed at D42 and D201. Using a live virus neutralization assay, broad cross-reactivity is detectable against all variants at D42. At D201, cross-reactive antibodies are detectable in almost all participants against Alpha, Gamma and Delta variants (94%) and the Beta variant (83%) and in a smaller proportion against Omicron (44%). Results are similar with the pseudovirion assay. These data suggest that two doses of 3.75 µg CoVLP+AS03 elicit a durable and cross-reactive response that persists for at least 6 months post-vaccination.


Assuntos
COVID-19 , Vacinas de Partículas Semelhantes a Vírus , Vacinas Virais , Adulto , Humanos , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Imunidade , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
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